Scientific method and Life What do you recall about… science? What does it include? What does it NOT include? How do you present your findings? To what are you going to apply these strategies in this course? Chapter 1 in text

What does a Scientist do?

“Science uses empirical data, logical arguments, and skepticism to find the best possible explanations about the natural world. Scientific knowledge is subject to change as new evidence becomes available. [Such as?] Scientists have ethical traditions that value truthful reporting, peer review, and making public the results of their work.” 1 Do you understand the above statement? Would you be able to explain each concept in bold? 1 “Enduring understanding” from a previous DCPS biology curriculum. The current version says, “Classify science as Consistent, Observable, Natural, Predictable, Testable, and Tentative. old timey autoclave

SCIENTIFIC METHOD (experimental design) And SCIENCE FAIR

Scientific Method Hypothesis - A testable explanation of a question or problem. - Requires some knowledge of the system. Knowledge can come from research, e.g.? or personal observation. Observation (seen) vs. inference (generalized), based on…. Inductive Reasoning - An extension from a set of particulars to a general rule. i.e. repeated patterns enabling predictions e.g. Things keep falling, so there must be something causing it. (gravity) Deductive Reasoning - Starting from general rules to interpret specific cases. e.g. I know about gravity, so I assume this ___ will fall if dropped.

Experiment Testing a hypothesis by collecting information under controlled conditions. Independent variable: - the condition that is changed. Dependant variable: - the measured difference resulting from the independent variable. Experimental group: - Subject to conditions varied one at a time. Control group: - Treated to ‘standard’ conditions of the independent variable. Controlled variables: - All environmental factors that might influence the outcome, and will be kept the same for all groups. Data: -Experimental results, observations. Numerical data include length, time, volume, etc.: quantitative Observational data include such things as behaviors: qualitative.

Theory “…when a hypothesis is repeatedly verified over time and through many separate experiments: valid theories enable scientists to predict new facts and relationships….” When technically used, there is no such thing in science as “just a theory”. “Theories are well supported explanations and laws are well supported descriptions.”

Decimal prefixes: atto femto pico nano micro milli-1/1, centi-1/ deci-1/100.1 (unit)(1) deka-1010 hecto kilo-1, mega ,000,000 giga ,000,000,000 tera ,000,000,000,000 peta ,000,000,000,000,000 exa ,000,000,000,000,000,000 How many micrometers in a millimeter? How many milligrams in a kilogram? Notice the ease of conversions within the metric system.

Go to Power Point about graphing.

What does it mean to be “alive”? Which of the following is/are alive? Why or why not?

commons.wikimedia.org/wiki/Image:Ostrich_egg.jpg

It’s ALIVE! Requires energy (from food, or from inorganic sources) Requires nutrients (even if energy is from, say, the sun) Metabolism Builds molecules… breaks molecules down Maintains homeostasis e.g. pH, fluid and nutrient levels, temperature?... Reproduction (self replicating), using the universal Genetic Code. Growth and/or development (If it divides but never gets bigger…) Some undergo profound metamorphosis. Response to the environment/Adaptation e.g. shivering, phototropism, kinesis… Evolution is a long-term response to the environment May be structural or behavioral By default, such things also show organization Cellular at least, up to systemic) To be alive a thing must meet all of these criteria.

Hierarchy of Life

Atom, Molecule, Organelle, Cell, Tissue, Organ, Organ system, Organism, Population, Community, Ecosystem, Biome, Biosphere. We will be looking at all of these.

What does it mean to be alive? An unfamiliar object came back on a space ship: How do you determine if it is “alive”? Distinguish between inductive and deductive reasoning, contriving an example involving study skills. Devise an experiment, including the hypothesis, independent variable, dependent variable, and control group, and identify controlled variables. Now do it, and you are done with science fair! These are questions to guide your study. It might be even better to come up with your own… How many ‘picos’ in a ‘tera-’?

Benchmark SC.912.N.1.1: Define a problem based on a specific body of knowledge, for example: biology, chemistry, physics, and Earth/space science, and do the following: pose questions about the natural world; conduct systematic observations; examine books and other sources of information to see what is already known; review what is known in light of empirical evidence; plan investigations; use tools to gather, analyze, and interpret data (this includes the use of measurement in metric and other systems, and also the generation and interpretation of graphical representations of data, including data tables and graphs); pose answers, explanations, or descriptions of events; generate explanations that explicate or describe natural phenomena (inferences); use appropriate evidence and reasoning to justify these explanations to others; communicate results of scientific investigations; and evaluate the merits of the explanations produced by others They are not usually this long!

Enduring Understandings Observations lead to inferences; Inferences can be tested. Essential Questions What inferences can we make about living things from our observations?

These are the highlighted/emboldened words from this presentation. The ones in orange are from the DCPS syllabus, and may be duplicates. They are all fair game for vocabulary quizzes. I have not provided verbatim definitions: You will have to actually grasp the meanings, from lecture, overheads, the text, and and/or any other outside resources. empirical datadependant variable energy logical argumentcontrolled variables nutrients skepticismdata metabolism hypothesisquantitative homeostasis researchqualitative reproduction observationtheory response inferencelaw consistent inductive reasoningmicro- observable deductive reasoningmilli- natural experimentcenti- predictable control groupnano- testable experimental groupkilo- tentative independent variablemega-